On my Altar in my room, i have a gorgeous fountain, and in it are shells that i have collected from the beach. I have been charging my fountain for days now, giving it some of my energy every day, and now, the water that runs over the shells is causing them to change colour, they are all slowly changing. Does anyone know what this could mean?

I am assuming here that you are talking about shells you gathered on the beach by the ocean? If that is the case the answer is simply that you have taken shells meant to exist in salt water and put them into fresh water. The change in salinity will cause the colors to fade and eventually the shells will deteriorate.